Fuel-burning appliances, including wood stoves and pellet stoves, require an exhaust system in order to vent combustion by-products, such as noxious gases, fine ash, and water vapor, to the outside of the structure containing the appliance. In addition, combustion air must be supplied to the appliance to properly fuel the fire. In a typical pellet stove installation, the appliance includes a mechanical fan to both blow the combustion by-products out through the exhaust pipe and to draw combustion air in through a separate air inlet pipe, while wood-burning appliances do not have a fan and are naturally drafting. However, it is also typical to create two different openings in the wall or ceiling adjacent to the heating appliance, one for routing the exhaust outlet, and one for routing the combustion air inlet.
It would be desirable to have a single component that provides two paths—one for the exhaust outflow, and one for the combustion air inflow, such that only a single opening in the wall or ceiling is required.